In production of a semiconductor device, specifically in processing steps of chemical vapor deposition (CVD), surface reforming and the like, a substrate support device is provided in a semiconductor production apparatus. In the case where the substrate support device is used in the state of being heated, a substrate support device having a built-in heating element is provided in the semiconductor production apparatus. Such a substrate support device has a structure in which a plate formed of a metal or ceramic material is supported by a shaft. There are cases where a plasma electrode or a heating element is provided in the plate and is connected to a control device provided outside the semiconductor production apparatus via a line provided in the shaft.
For a plate of such a substrate support device, bulk ceramics such as aluminum nitride (AlN), aluminum oxide (Al2O3) and the like are often used. However, in order to provide a plasma electrode or a heating element in the substrate support device, the inside of the plate needs to have a complicated structure. It is difficult to process bulk ceramics into such a complicated structure. By contrast, a metal plate allows a complicated structure to be formed therein easily, and also at lower cost than bulk ceramics. In the case where a metal plate is used, a surface of the metal plate on which a substrate is to be mounted needs to be covered with an insulating material, and contamination of the substrate with metal caused by contact needs to be reduced. For example, Japanese Laid-Open Patent Publication No. 2007-184289 describes a metal plate which is given an alumite treatment (an anodizing).
However, when a metal plate is anodized, the anodized film has a thickness of about 50 to 75 μm and a withstand voltage of about 0.8 to 1 kV. It is difficult to realize a higher withstand voltage. For producing a precision semiconductor device of, for example, the 25 nm process or the like, the metal plate needs to be covered with a material having a high thermal resistance in order to prevent the metal from being contaminated.
The present invention for solving the above-described problems has an object of providing a substrate support device formed of a metal and having a high withstand voltage and a high thermal resistance.